1Build the arm by servos and Legos.
Print some shapes to connect Lego and servos.
connect servo parts to build a sample 3DoF robot arm.
Extend it to a 7DoF robot arm.
2Prepare an Arduino board and PCA9685 to drive servos
Check Arduino pin A4 -> PCA9685 SDA , pin A5->PCA9685 SLC. GRD -> GRD, 5V->5V
3Set up a URDF model of the arm in your computer
Prepare an Ubuntu Linux virtual machine and install ROS.
Install URDF plugin to Solidworks.
Build a robot arm in Solidworks and Export to a URDF file.
Set up every link
Press button "Preview and Export" to generate joint configurations.
Save the project and copy the file folder to Linux ROS catkin workspace.
Check the folder as a ROS package.
roslaunch urdf_tutorial display.launch model:=<the robot arm filename>.urdf
move the model by joint_state_publisher
So, extend it to a 7DoF robot arm model.
4Config a moveit node for the arm to feature motion-planning ability
The following instruction references http://docs.ros.org/kinetic/api/moveit_tutorials/html/doc/setup_assistant/setup_assistant_tutorial.html
(1)To start the MoveIt! Setup Assistant
roslaunch moveit_setup_assistant setup_assistant.launch
(2) Load the urdf file.
(3) Set up the configures of self-collisions, virtual joints, planning groups, etcs.
config the virtual joint as : child: base_link, frame: world, type: fixed because our robot type is an industrial arm.
(4) Generate the configuration package.
(5) Examine the configuration
> cd catkin_ws/src/0321_moveit_config/launch
> roslaunch demo.launch
to start RViz:
yes, the motion planner for our robot arm works.
5Code a ros-control node with Arduino to control servos of the arm
6Calibrate the robot